The aim of this project is to develop a practical model of myeloid cell mediated immune surveillance to investigate the trafficking signals used by these cells at rest and during disease states (i.e. infection, allergic, and inflammatory reactions). Also part of this project is a related initiative to study the role of phagocyte oxidants in the development of pulmonary allergic/asthmatic response to allergen challenge.Projects: 1. In vitro proliferation and differentiation of hematopoietic progenitors into macrophages/dendritic cells.2. Characterization of the functional maturation of dendritic cells, comparing homeostasis to disease states.3. Ex vivo transfer of differentiated cells into recipient mice (wild type, p47phox-/- ). 4. Macrophage/dendritic cell apoptosis5. In vitro model of dendritic cell phagocytosis of host leukocytes6. Characterize granulocyte survival, apoptosis and clearance in inflamed tissue.7. Develop a model of asthma in the mouse to delineate the role of phagocyte (neutrophil, monocyte, macrophage) oxidants in this disease process.